It is difficult to dispute the effectiveness of the scientific method when it comes to medicine. So many of the diseases and ailments that used to kill us have been eliminated. Yet the actual process whereby medicines and treatments are deemed to be efficacious and safe, the very heart of the scientific method – clinical trials, can be a heartbreaking business, as in this case, where two cousins with the same variety of cancer where by chance, seperated – one into the control group and one into the group receiving the new and as it turned out effective drug.

Growing up in California’s rural Central Valley, the two cousins spent summers racing dirt bikes and Christmases at their grandmother’s on the coast. Endowed with a similar brash charm, they bought each other matching hardhats and sought iron-working jobs together. They shared a love for the rush that comes with hanging steel at dizzying heights, and a knack for collecting speeding tickets.

And when, last year, each learned that a lethal skin cancer called melanoma was spreading rapidly through his body, the young men found themselves with the shared chance of benefiting from a recent medical breakthrough.

Only months before, a new drug had shown that it could safely slow the cancer’s progress in certain patients. Both cousins had the type of tumor almost sure to respond to it. And major cancer centers, including the University of California, Los Angeles, were enrolling patients for the last, crucial test that regulators required to consider approving it for sale.

“Dude, you have to get on these superpills,” Thomas McLaughlin, then 24, whose melanoma was diagnosed first, urged his cousin, Brandon Ryan. Mr. McLaughlin’s tumors had stopped growing after two months of taking the pills.